Sanding apparatus with adjustable flexibility

ABSTRACT

A hand-held sanding apparatus has an adjustable flexibility. The sanding apparatus includes a flexible handle with a plurality of preformed rod channels. One or more rods are configured for insertion into the rod channels, wherein the one or more rods adjust a flexibility of the sanding apparatus. A flexible base member is attached to a lower surface of the flexible handle and includes a precisely smooth bottom surface configured for attachment to an abrasive material. The flexible base member may comprise a polycarbonate material, and the flexible handle may comprise a rubber material.

RELATED APPLICATION

This application claims priority under 35 U.S.C. § 119 to U.S. Provisional Application No. 63/356,915 entitled, “SANDING APPARATUS WITH ADJUSTABLE FLEXIBILITY,” filed Jun. 29, 2022, and hereby expressly incorporated by reference herein.

FIELD

This application relates to an apparatus for sanding, and more particularly, to a hand-held sanding block with adjustable flexibility.

BACKGROUND

Hand-held sanding blocks are commonly used for sanding various types of surfaces, such as vehicles, furniture, buildings, etc. In its simplest form, a sanding block has a flat side for attaching adhesive sanding material, such as sanding paper, and an opposing side for use as a handle. The sanding block helps distribute sanding pressure more evenly and maintain a flatter surface than sandpaper alone. The sanding block also provides for greater application of force to a surface. However, a problem arises when the surface to be sanded is curved, and the sanding block is not flexible to conform to the curve. In addition, different surfaces being sanded have varying degrees of curvature, from highly curved to nearly flat. A sanding block having flexibility increases its utility for sanding such curved surfaces. In addition, a sanding block that is not only flexible, but includes a means to adjust the flexibility, further increases its utility and reduces the need to have multiple variations of the tool. Various solutions have been proposed in the past but each has distinct disadvantages.

In one particular example, U.S. Pat. No. 6,544,113 discloses a sanding apparatus with adjustable flexibility including a handle and a thin, stainless steel base member including two end attachment brackets on a top side of the base member for securing the base member to the handle. Stainless steel rod reception brackets are also attached to a top side of the base member including rod reception channels. The handle includes corresponding rod reception channels that are designed for alignment with the bracket rod reception channels when the base member brackets are inserted into the handle. Plastic rod reception tubes are positioned through the bracket rod reception channels and the aligned handle rod reception channels. Steel flexibility rods may then be inserted into the plastic rod reception tubes to adjust the flexibility of the sander. Abrasive, sanding material is attachable to a bottom side of the base member.

However, the sanding apparatus described in this U.S. Pat. No. 6,544,113 has various disadvantages in practice. Thus, there is a need for an improved sanding apparatus with more utility, durability, and ease of use.

SUMMARY

In one aspect, a sanding apparatus includes a flexible handle including a plurality of rod channels, wherein the plurality of rod channels is formed into the flexible handle. The sanding apparatus also includes a flexible base member including a smooth top surface that is attached to a lower surface of the flexible handle and a smooth bottom surface configured for attachment to an abrasive material.

In another aspect, a sanding apparatus includes a flexible handle including a plurality of rod channels, wherein the plurality of rod channels is preformed into the flexible handle, and a flexible base member attached to a lower surface of the flexible handle, wherein the flexible base member is a polycarbonate material. The sanding apparatus further includes one or more rods configured for insertion into one or more of the plurality of preformed rod channels, wherein the one or more rods adjust a flexibility of the sanding apparatus.

In another aspect, a method of manufacturing a sanding apparatus includes manufacturing a flexible handle including a plurality of rod channels, wherein the plurality of rod channels is preformed into the flexible handle, by: in a lower mold, positioning a manufacturing rod on each one of a plurality of rows of pegs; attaching an upper mold to the lower mold; and injecting a heated nitrile butadiene rubber (NBR) material in liquid form into the attached upper and lower molds, wherein the plurality of manufacturing rods forms the plurality of rod channels. The method further includes manufacturing a flexible base member by forming a thin sheet of polycarbonate material, wherein the thin sheet has a thickness of approximately ⅛ inch to 1/16 inch and attaching the flexible base member to a lower surface of the flexible handle.

In one or more of the above aspects, the flexible base member comprises a polycarbonate material and the flexible handle comprises a rubber material.

In one or more of the above aspects, one or more inflexible rods are configured for insertion into one or more of the plurality of preformed rod channels, wherein the one or more inflexible rods adjust a flexibility of the sanding apparatus.

In one or more of the above aspects, an elasticity of the rubber material of the flexible handle holds one or more rods in position within the one or more of the plurality of preformed rod channels.

In one or more of the above aspects, the flexible handle is inflexible when the plurality of rods is inserted into the plurality of preformed rod channels.

In one or more of the above aspects, the flexible handle comprises a top surface with at least a flat middle section WFT extending lengthwise, a lower support portion including the plurality of rod channels, and a gripping portion including two indentations on opposing sides of the handle, wherein the gripping portion is positioned between the top surface and the lower support portion.

In one or more of the above aspects, the flexible base member has a thickness in the range of approximately ⅛ inch to 1/16 inch.

In one or more of the above aspects, the flexible handle has a height of approximately 1.4 to 1.6 inches.

In one or more of the above aspects, the base member has a width W_(BM) equal to or less than the standard width of commercially available standard sanding paper.

In one or more of the above aspects, the base member has a length L_(BM) of approximately one of: 8 inches, 16 inches, or 24 inches.

In one or more of the above aspects, the flexible base member includes a smooth top surface that is attached to the lower surface of the flexible handle, and a smooth bottom surface configured for attachment to an abrasive material.

In one or more of the above aspects, the flexible handle includes a top surface including at least a flat middle section WFT extending lengthwise, a lower support portion including the plurality of rod channels, and a gripping portion including two indentations on opposing sides of the handle, wherein the gripping portion is positioned between the top surface and the lower support portion.

In one or more of the above aspects, the plurality of rows of pegs in the lower mold of the flexible handle form a plurality of cavities on the lower surface of the flexible handle.

In one or more of the above aspects, at least one rod is manufactured for each of the plurality of rod channels in the flexible handle.

In one or more of the above aspects, the flexible base member is attached to the lower surface of the flexible handle using one of: an adhesive, a heat process, or a combination of an adhesive and a heat process.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing summary, as well as the following detailed description of preferred embodiments of the invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there are shown in the drawings embodiments that are presently preferred. It should be understood, however, that the claims are not limited to the precise arrangements and instrumentalities shown.

FIG. 1 illustrates an exploded perspective view of exemplary embodiments of parts of a sanding apparatus with adjustable flexibility.

FIG. 2A illustrates a side perspective view of an exemplary embodiment of the sanding apparatus with adjustable flexibility.

FIG. 2B illustrates a perspective view of the lower surface of an exemplary embodiment of the sanding apparatus with adjustable flexibility.

FIG. 3 illustrates a side view of an exemplary embodiment of a first end of the sanding apparatus with adjustable flexibility.

FIG. 4 illustrates a side view of an exemplary embodiment of a flexibility adjustment rod for use with the sanding apparatus.

FIGS. 5A-C illustrate a perspective of example embodiments of varying rod ends for a plurality of rods.

FIG. 6 illustrates a flexibility simulation for an embodiment of the sanding apparatus having a length of 8 inches.

FIG. 7 illustrates a flexibility simulation for an embodiment of the sanding apparatus having a length of 16 inches.

FIG. 8 illustrates a flexibility simulation for an embodiment of the sanding apparatus having a length of 24 inches.

FIGS. 9A-C illustrate side perspective views of exemplary embodiments of the sanding apparatus with adjustable flexibility.

FIG. 10A illustrates a schematic block diagram of an embodiment of the handle of the sanding apparatus.

FIG. 10B illustrates a schematic block diagram of an embodiment of a mold to manufacture a plurality of handles.

FIG. 11 illustrates an embodiment of a method for manufacturing an embodiment of the sanding apparatus.

DETAILED DESCRIPTION

The word “exemplary” or “embodiment” is used herein to mean “serving as an example, instance, or illustration.” Any implementation or aspect described herein as “exemplary” or as an “embodiment” is not necessarily to be construed as preferred or advantageous over other aspects of the disclosure. Likewise, the term “aspects” does not require that all aspects of the disclosure include the discussed feature, advantage, or mode of operation.

Embodiments will now be described in detail with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the aspects described herein. It will be apparent, however, to one skilled in the art, that these and other aspects may be practiced without some or all of these specific details. In addition, well known steps in a method of a process may be omitted from flow diagrams presented herein in order not to obscure the aspects of the disclosure. Similarly, well known components in a device may be omitted from figures and descriptions thereof presented herein in order not to obscure the aspects of the disclosure.

Through repeated and prolonged use and experimentation, various disadvantages were ascertained in current sanding apparatuses with adjustable flexibility, such as that in the above described U.S. Pat. No. 6,544,113. First, to obtain the desired flexibility and conform to curved surfaces, the current sanders have a thin stainless steel base member. However, this thin stainless steel base member is prone to deformations and breakage. These deformations make it difficult to attach the abrasive sanding material to the stainless steel base member. In addition, the thin stainless steel, especially after repeated use and wear, becomes too weak to exert sufficient force on rough surfaces. This reduces the utility of the tool in that the thin metal yields to imperfections in the surface being sanded. This undermines the purpose of the tool which is to cause the surface being sanded to yield to the sanding block, removing imperfections, and produce a flat, smooth surface. The thin metal can also lead to undue wear and tear and even failure.

Second, in current sanding apparatuses with adjustable flexibility, the rod reception channels in the brackets must be aligned with the bracket rod reception channels in the handle. This alignment creates additional steps and increases difficulties in manufacture and assembly.

Third, in current sanding apparatuses with adjustable flexibility, the stainless steel brackets on the base member are prone to bending and even breaking from the base member. This bending or breaking of the brackets causes misalignment between the rod reception channels in the brackets and the bracket rod reception channels in the handle. The misalignment creates difficulties in inserting the adjustment rods into the plastic rod reception tubes. It may also loosen the attachment of the steel base member from the handle causing more difficulty in generating a smooth sanded surface.

In later renditions of these currently known sanding blocks, a plurality of cuts or indentations were positioned on a top gripping portion of the handle to enhance the flexibility of the handle portion. These cuts were prone to pinching a user and made it more difficult to apply pressure on the handle for sanding.

To address these disadvantages in currently known hand-held sanding blocks with adjustable flexibility, an improved sanding block with adjustable flexibility is described herein.

FIG. 1 illustrates an exploded perspective view of exemplary embodiments of parts of a sanding apparatus 100 with adjustable flexibility. A flexible handle 110 includes an upper gripping portion 102 and a lower support portion 104. The upper gripping portion 102 is configured for grasping and exerting pressure manually on the sanding apparatus 100. The lower support portion 104 of the handle 110 includes a relatively flat, rectangular bottom side 106 configured for attachment to a flexible base member 150. In one embodiment, a precision, smooth top surface 152 of the base member 150 is attached to the bottom side 106 of the handle 110 using an adhesive or using a heat process or a combination thereof. In another embodiment, the base member 150 and handle 110 are manufactured as one piece, e.g. using a multi-shot injection molding process wherein a first material is injected into a mold to create the base member 150 and a second material is injected into the mold to create the handle 110.

The base member 150 further includes a precise smooth lower surface 154 configured for attachment of an abrasive material, such as sanding paper. The abrasive material is attached to the surface 154 of the base member 150 using adhesive, such an adhesive backed sandpaper.

The handle 110, and in specific, the lower support portion 104 of the handle 110, includes a plurality of preformed rod channels 120 that extend lengthwise from a first end 160 of the handle 110 to a second end 162 of the handle 110. The plurality of rod channels 120 is preformed within the material of the handle 110 during manufacturing of the handle 110, e.g., through injection molding or other types of manufacturing processes. Since the plurality of rod channels 120 are preformed within the handle 110, there is no need for the base member 150 to include brackets or rod channels within the brackets as in prior configurations of sanding apparatuses. And the sanding apparatus 100 no longer has the problems with bending or breakage of the base member brackets. Furthermore, the difficulties of aligning the rod channels in the base member brackets to the rod channels in the handle are eliminated.

In an embodiment, the handle 110 comprises a flexible material, such as rubber material, or more particularly a foam rubber material or nitrile butadiene rubber (NBR). For example, the flexible material of the handle 110 may have a Shore A Hardness Scale in a range of 20 A to less than 40 A or more particularly, a Shore A Hardness Scale of approximately 30 A. The flexible material is thus categorized as soft to medium soft along the Shore A Hardness Scale. In another embodiment, the flexible material of the handle 110 may have a Shore A Hardness in a range of 40 A to 60 A or more particularly, a Shore A Hardness in a range of 45 A to 55 A or more particularly, approximately 50 A. This generates flexibility in the handle 110 while maintaining durability. The flexible material of the handle 110 also provides chemical resistance, such as to residues from sanded surfaces and from paint, solvents and other chemicals typically present in an automotive body repair facility.

One or more flexibility adjustment rods 130 may be inserted into one or more of the plurality of rod channels 120 in the handle 110 to adjust flexibility of the sanding apparatus 100. The rods 130 comprise a strong, inflexible material, such as steel, titanium, iron, or a metal alloy of one or more metals, or a polycarbonate or other polymer compound material, etc. An elastic cap 140 is configured to fit snugly onto an end of each rod 130 for protection of the rod and user from scraping. The elasticity of the cap exerts circumferential force against the rod 130 to maintain the cap 140 securely onto the rod 130. The elastic cap 140 also provides guidance to indicate when the rod 130 is fully inserted into a rod channel 120.

When the rod 130 is inserted into one of the plurality of rod channels 120, the elasticity of the flexible material of the handle 110 exerts circumferential force on the rod 130 to hold the rod 130 in position. Alternatively or additionally, in an embodiment, the fitted cap 140 may be configured to extend partially into the opening of the rod channel 120 when the rod is inserted into the rod channel 120, e.g. such that the fitted cap is at least partially wedged into the opening of the rod channel 120. Due to the compression of the rod channel 120 on the fitted cap 140, the elasticity of the fitted cap 140 generates a force against the inner circumference of the rod channel 120 to hold the rod 130 in place.

The flexible base member 150 comprises a polycarbonate material. Polycarbonate has an ability to undergo significant deformation without cracking or breaking. It has an extremely high impact strength, e.g., compared to plexiglass or other acrylics. Polycarbonate is also highly resistant to acids and other chemicals with a low level of flammability. This combination of strength and flexibility in the material provides a unique advantage to the base member 150. The base member 150 is flexible enough to conform to curved surfaces without deformity while also maintaining strength to apply pressure to protrusions in a sanding surface.

The base member 150, due to the flexibility of the polycarbonate material, may have a thickness in a range of approximately ⅛ inch to 1/16 inch. This thickness of the base member 150 is greater than stainless steel base members of currently known sanding apparatuses. Thus, the base member 150 in this embodiment has a greater thickness and strength while maintaining flexibility.

FIG. 2A illustrates a side perspective view of an exemplary embodiment of the sanding apparatus 100 with adjustable flexibility. The sanding apparatus has a height H_(SA) between 1.5 inches to 2.0 inches. The base member 150 may have a thickness or height H_(BM) in a range of approximately ⅛ inch to 1/16 inch or more particularly, 0.08 inches. This thickness provides strength but flexibility to the base member. The handle 110 has a height of approximately 1.4 to 1.6 inches, or more particularly 1.5 inches. This height makes it easier to grip the handle and apply pressure to the sanding surface.

FIG. 2B illustrates a perspective view of the lower surface of an exemplary embodiment of the sanding apparatus 100 with adjustable flexibility. The lower surface of the sanding apparatus 100 illustrated shows the lower or bottom surface 154 of the base member 150. In one embodiment, the base member 150 has a width W_(BM) equal to or less than a standard width of commercially available standard sanding paper. For example, the base member 150 has a width W_(BM) between 2 inches to 3 inches wide, and more particularly 2.625 inches wide. Current standard sanding paper is approximately 3 inches wide. With the base member 150 having a width W_(BM) less than 3 inches, the standard-sized sanding paper may extend the width of the base member 150 and include excess on the sides to fold or curl over the base member 150 and/or handle 110. In other embodiments, the base member 150 may have a width W_(BM) of 3 inches to fit a standard sized 3 inch sanding paper without folding. The base member 150 may thus fit within the width of commercially available sanding paper. However, the base member 150 and/or the sanding apparatus 100 are not constrained to the widths described herein. Other widths of the sanding apparatus 100 and/or the base member 150 may also be implemented depending on the application.

The length L_(BM) of the base member 150 is approximately 16 inches in this example, but other embodiments may include other lengths, such as 8 inches or 24 inches, which are appropriate for different sizes, locations and shapes of the vehicle panel or other object being sanded. The sanding apparatus 100, and/or the handle 110 and/or the base member 150 are not constrained to the lengths described herein. Other lengths of the sanding apparatus 100 may also be implemented depending on the application.

FIG. 3 illustrates a side view of an exemplary embodiment of a first end 160 of the sanding apparatus 100 with adjustable flexibility. The handle 110 includes two gripping portions 170 a-b. The gripping portions 170 a-b are between the top surface of the handle 110 and a lower support portion 104 of the handle 110. The gripping portions 170 a-b include opposing lengthwise indentations on each side of the handle 110 for easier gripping and maneuvering of the sanding apparatus 100. The gripping portions 170 a-b may extend lengthwise to a full length of the handle 110 as shown or to only a portion of the length of the handle 110.

In an embodiment, the handle 110 includes rounded top edges 180 lengthwise that extend from the indentations of the gripping portions 170 a-b and meet at a relatively flat top surface 172 of the handle 110. For example, the side profiles of the handle 110 may have a rounded or contoured lengthwise top edges 180 that end with the relatively flat top surface 172 of the handle 110. The top surface 172 of the handle 110 includes at least a flat middle section W_(FT), extending lengthwise and parallel to the base member 150. The flat middle section W_(FT) may have a length extending from one end 160 of the handle 110 to the other end 162 of the handle 110, as shown in FIG. 3 , or extend partially lengthwise. The flat middle section W_(FT) may have a width of 1 inch to 2 inch, or more particularly 1.5 inches. The flat middle section W_(FT) generates a more uniform force to be applied to a sanding surface when a user's hand, e.g. palm, presses along the flat middle section W_(FT). In addition, the flat middle section W_(FT) lowers a profile of the handle 110 for easier grasping by a user's fingers of the gripping portions 170 a-b, especially for smaller hands. The height H_(GP) of the handle 110 from the top surface 172 of the handle 110 to a start of the lower support 104 of the handle 110 may also be decreased from prior known blocks, e.g. to a height H_(GP) of 1 inch −1.25 inches, to further ease grasping of the gripping portions 170 a-b. This decreased height H_(GP) helps a user to grip the handle and apply pressure to the sanding surface.

The side view of the sanding apparatus 100 also illustrates the lower support portion 104 of the handle 110. The support portion 104 is positioned between the gripping portions 170 a-b of the handle 110 and the base member 150. The support portion 104 includes the plurality of preformed rod channels 120. A plurality of rods 130 with end caps 140 are shown inserted into the plurality of channels 120. In this embodiment, the support portion 104 includes three rod channels 120. However, more or less rod channels 120 may be implemented in other applications. For example, two rod channels 120 may be employed for a shorter sanding apparatus 100, such as an 8 inch length sanding apparatus 100. In another example, additional rod channels 120 may be implemented with wider sanding apparatus, e.g. a sanding apparatus having a width of 3 inches or more.

FIG. 4 illustrates a side view of an exemplary embodiment of a rod 130 for use with the sanding apparatus 100. The rod 130 is cylindrically shaped and sized for placement in at least one of the plurality of rod channels 120. The rod 130 comprises a stainless steel, titanium, iron, or other relatively inflexible material in comparison to the material of the handle 110. In one embodiment, the rod 130 has a length L R equal to approximately 16 inches for a sanding apparatus of length L_(SA) of 16 inches. In other embodiments, the length LR of the rod 130 may be 8 or 24 inches for a sanding apparatus 100 of length L_(SA) of 8 or 24 inches, respectively. Thus, in an embodiment, the length L R of the rods for a sanding apparatus 100 equals a length L_(SA) of the sanding apparatus 100 or at least a length of the support portion 104 of the sanding apparatus 100. In other embodiments, the length L R of the rod 130 is at least ⅔ of the length of the support portion 104 of the handle 110. For example, the rod 130 may be slightly shorter than the support portion 104 to fit within the rod channels 120. In another example, the rods 130 may be slightly longer than a length of the support portion 104 of the sanding apparatus 100, e.g. such that a portion of the rod 130 extends outward from an opening of a rod channel 120 for easy removal and insertion. Other lengths of the sanding apparatus 100 may also be implemented depending on the application. In this embodiment, the rods 130 and rod channels 120 are cylindrical but may have alternate shapes, such as rectangular or octagonal.

FIGS. 5A-C illustrate a perspective of example embodiments of varying rod ends 132 for the plurality of rods 130. In one embodiment, the plurality of rods 130 have a same diameter D_(R), such as 0.188 inch as shown in FIG. 5A. The plurality of rod channels 120 in the handle 110 will then also have a same or similar diameter configured to fit the rods 130. For example, the diameter D_(RC) of each of the plurality of the rod channels 120 may be 0.188 inch or in a range of 0.178 inch-0.198 inch diameter, to allow for insertion of the rods 130. When the rods 130 have a same diameter, each inserted rod 130 decreases or decrements the flexibility of the sanding apparatus 100 by an approximately same proportion.

In another embodiment, the plurality of rods 130 have varying diameters to affect the flexibility of the sanding apparatus 100 by different proportions. For example, a first rod 130 may have a diameter D_(R1) of 0.188 inches (+/−0.01 inches tolerance) as shown in FIG. 5A, a second rod may have a diameter D_(R2) of 0.094 inches (+/−0.01 inches tolerance) as shown in FIG. 5B, and a third rod may have a diameter D_(R3) of 0.36 inches (+/−0.01 inches tolerance) as shown in FIG. 5C. The plurality of rod channels 120 may also have varying diameters configured to fit the rods, e.g. such as 0.188 inch diameter, 0.094 inch diameter and 0.36 inch diameter (each with at least +/−0.01 inches tolerance) to allow for insertion of the rods 130 with varying diameters. Each inserted rod 130 then will decrease or decrement the flexibility of the sanding apparatus 100 by different proportions. The sanding apparatus 100 may accommodate a plurality of rods with different diameters or two rods with a same diameter and a third with a different diameter or other combinations. The various diameters of the plurality of rods 130 and the plurality of rod channels 120 is exemplary, and other diameters may be implemented depending on the application.

In another embodiment, rod insertion tubes may be employed with rods 130 and the plurality of channels 120. The rod insertion tubes may be installed in one or more of the plurality of channels 120. The rods 130 are then inserted into the rod insertion tubes. In an embodiment, the rod insertion tubes have a same outer diameter to snugly fit within the plurality of rod channels 120. However, the rod insertion tubes have a varying inner diameter to fit rods 130 having varying diameters. The plurality of rod channels 120 may thus have a same diameter but still accommodate rods of varying diameters.

FIG. 6 illustrates a flexibility simulation for an embodiment of the sanding apparatus 100 including the handle 110 and base 150. In this embodiment, the sanding apparatus has a length of 8 inches. The handle 110 has the approximate dimensions of a height of 1.5 inches and a width of 2.25 inches. The handle 110 comprises an NBR material, as described herein, having an elastic modulus of approximately 4 megapascals (MPa) and approximately Shore A hardness 50. The base 150 is a polycarbonate material.

In this simulation, the plurality of rod channels 120 are empty and do not include the inflexible rods 130. The simulation illustrates the resultant deformation of the sanding apparatus with an applied force of 10 pounds (lbs.) on a center, top portion 600 of the handle 110 of the sanding apparatus 100 while the ends 602 a, 602 b of the sanding apparatus 100 are maintained at a same parallel level. The largest deformation shown at the center, top portion 600 of the handle 110 is approximately 3.3 millimeters (mm) or 0.13 inches.

FIG. 7 illustrates a graph of a flexibility simulation for another embodiment of the sanding apparatus 100 including the handle 110 and base 150. In this embodiment, the sanding apparatus 100 has a length of approximately 16 inches, and the handle 110 has the approximate dimensions of a height of 1.5 inches and a width of 2.25 inches. The handle 110 comprises an NBR material, as described herein, having an elastic modulus of approximately 4 megapascals (MPa) and approximately Shore A hardness 50. The base 150 is a polycarbonate material.

In this simulation, the plurality of rod channels 120 are empty and do not include the rods 130. The simulation illustrates the resultant deformation of the sanding apparatus with an applied force of 10 lbs. on a center, top portion 610 of the handle 110 of the sanding apparatus 100 while the ends 612 a and 612 b are maintained at a same parallel level. The largest deformation shown at the center, top portion 610 of the handle 110 is approximately 15.5 millimeters (mm) or 0.61 inches. The sanding apparatus 100 is thus flexible but the handle still retains its shape.

Preferably, in an embodiment, with the plurality of rods 130 inserted into the plurality of channels 120, the sanding apparatus 100 does not bend or bends 1 mm or less with an applied force of 10 pounds (lbs.) on a center, top portion 600 of the handle 110. The sanding apparatus 100 is thus inflexible and resistant to bending with the insertion of a corresponding rod 130 in each of the plurality of rod channels 120. One or two rods 130 may be inserted to obtain a flexibility between the flexible, approximately 15.5 mm bend of the block and the inflexible block with a bend of 1 mm or less.

FIG. 8 illustrates a graph of a flexibility simulation for another embodiment of the sanding apparatus 100 including the handle 110 and base 150. In this embodiment, the sanding apparatus 100 has a length of approximately 24 inches, and the handle 110 has the approximate dimensions of a height of 1.5 inches and a width of 2.25 inches. The handle 110 comprises an NBR material, as described herein, having an elastic modulus of approximately 4 megapascals (MPa) and approximately Shore A hardness 50 A. The base 150 is a plate of polycarbonate material.

In this simulation, the plurality of rod channels 120 are empty and do not include rods 130. The simulation illustrates the resultant deformation of the sanding apparatus with an applied force of 10 pounds (lbs.) on a center, top portion 620 of the handle 110 of the sanding apparatus 100 while the ends 622 a and 622 b are maintained at a same parallel level. The largest deformation shown at the center, top portion 610 of the handle 110 is approximately 46.6 millimeters (mm) or 1.83 inches. The sanding apparatus 100 is thus flexible but the handle still retains its shape.

Preferably, in an embodiment, with the plurality of rods 130 inserted into the plurality of channels 120, the sanding apparatus 100 in this embodiment is inflexible and does not bend or bends 1.5 mm or less with an applied force of 10 pounds (lbs.) on the top portion 600 of the handle 110. One or two rods 130 may be inserted to obtain a flexibility between the approximately flexible 15.5 mm bend and the inflexible a bend of 1.5 mm or less.

FIGS. 9A-C illustrates side perspective views of exemplary embodiments of the sanding apparatus 100 with adjustable flexibility. In FIG. 9A, the sanding apparatus 100 has a length L_(BM) of 8 inches. In this example, the sanding apparatus 100 has three rod channels 120 a-c for insertion of rods 130 a-c. The middle rod 130 b and rod channel 120 b have a diameter of approximately 3/16 inch, and the end rods 130 a, 130 c and rod channels 120 a, 120 c have a diameter of ⅛ inch. With these rods 130 a-c inserted, the sanding apparatus 100 with length L_(BM) of 8 inches is inflexible and does not bend or bends 0.5 mm or less with an applied force of 10 lbs. on a center, top portion 600 of the handle 110.

In FIG. 9B, the sanding apparatus 100 has a length L_(BM) of 16 inches. In this example, the sanding apparatus 100 has three rod channels 120 a-c for insertion of rods 130 a-c, and each of the three rods 130 a-c and rod channels 120 a-c have a diameter of approximately 3/16 inch. With these rods 130 a-c inserted, sanding apparatus 100 with length L_(BM) of 16 inches is inflexible and does not bend or bends 1 mm or less with an applied force of 10 lbs. on a center, top portion 600 of the handle 110.

In FIG. 9C, the sanding apparatus 100 has a length L_(BM) of 24 inches. In this example, the sanding apparatus 100 has three rod channels 120 a-c for insertion of rods 130 a-c, and each of the three rods 130 a-c and rod channels 120 a-c have a diameter of approximately ¼ inch. With these rods 130 a-c inserted, sanding apparatus 100 with length L_(BM) of 24 inches is inflexible and does not bend or bends 1.5 mm or less with an applied force of 10 pounds (lbs.) on a center, top portion 600 of the handle 110.

Though the rod channels 120 a-c are described as having a same diameter as the rods 130 a-c, the rod channels 120 a-c may be formed with a slightly small diameter, e.g., such as 5%-10% smaller diameter. The rod channels 120 a-c hold the rods 130 a-c through the elastic force of the NBR material of the handle 110 pressing against the rods 130 a-c. So the rod channels 120 a-c must have a diameter sufficiently large to insert the rods 130 a-c but also sufficiently small to hold the rods 130 a-c in place.

As shown in FIGS. 9 a-c , a diameter of one or more of the rods 130 needs to increase as the length L_(BM) of the sanding apparatus 100 increases to maintain the inflexibility of the sanding apparatus with the rods 130 a-b inserted. Additionally and/or alternatively, the number of rods 130 may be increased to maintain the inflexibility of the sanding apparatus with the rods 130 a-b inserted. For example, the sanding apparatus 100 with the length L_(BM) of 24 inches may include four or five rods 130 a-c having a diameter of approximately 3/16 inch, e.g., rather than three rods having a diameter of approximately ¼ inch. In another example, a sanding apparatus 100 with the length L_(BM) of 30 inches may include four or five rods 130 a-c having a diameter of approximately ¼ inch or may include three rods having a diameter of approximately ⅓ inch. The diameter of the rods 130 may also vary depending on their material, such as steel, titanium, iron, or a metal alloy of one or more metals, etc. The sanding apparatus 100 may thus have a different number and/or a different diameter of rods 130 depending on a length L_(BM) of the sanding apparatus and a material of the rods 130 so that the plurality of rods 130 maintain the inflexibility of the sanding apparatus 100 with the rods 130 inserted.

FIG. 10A illustrates a schematic block diagram of an embodiment of the handle 110 of the sanding apparatus 100. In this embodiment, a bottom surface 1010 of the handle 110 includes a plurality of cavities 1000 formed in the bottom side 1010 of the handle 110 during manufacturing. In an embodiment, the plurality of cavities 1000 are formed to a depth of the rod channels 120 in the lower support portion 104 of the handle 110. The cavities 1000 may be formed along one or more rows parallel to one or more of the plurality of rod channels 120.

FIG. 10B illustrates a schematic block diagram of an embodiment of a mold 1020 to manufacture a plurality of handles 110 of the sanding apparatus 100. In this embodiment, the mold 1020 includes a plurality of individual handle molds 1030 a-d. Each of the handle molds 1030 a-d includes a plurality of pegs 1022 that are formed in a number of rows 1024 a-c. In one example, the pegs 1022 have a height of no more than the lower support portion 104 of the handle 110, e.g., 0.5 inch to 0.25 inch. More particularly, the pegs 1022 may have a height of no more than a height from the base member 150 to the rod channels 120, e.g. 0.25 inch to 0.125 inch.

In an embodiment, the number of rows 1024 a-c of the pegs 1022 corresponds to the number of rods 130. The rows 1024 extend lengthwise along the handle 110 and are spaced equally distant apart along a width of the handle 110. During manufacturing, a manufacturing rod is positioned on each of the rows 1024 of pegs 1022, wherein a first end of the rod extends at least to a first end of the mold 1030 or overhangs the mold 1030 of the handle 110. This position creates the opening of the rod channel 120. A second end of the manufacturing rod is positioned within a last peg 1026 of a row 1024 and does not create an opening in a second end of the mold 1030. The manufacturing rods are sized in diameter equally to the plurality of rods 130 for the sanding apparatus 100. In another embodiment, the manufacturing rods may be sized slightly larger or smaller than the diameter of the plurality of rods 130.

The pegs 1022 may include a slot for insertion of the manufacturing rod to hold the rod in place. An end peg 1026 may include a concave slot with three sides to help form an end of the rod channel 120. The NBR material is then injected into the mold 1030, and the manufacturing rods preform the plurality of rod channels 120 in the material of the handle 110. The rod channels 120 are thus preformed and sized to fit the inflexible rods 130. The manufacturing rods may comprise a metal or rubber and be repetitively used during the manufacturing process.

The pegs 1022 form the plurality of cavities 1000 in the bottom surface 1010 of the handle 110 shown in FIG. 10A. The plurality of cavities 1000 may help increase the flexibility of the sanding apparatus 100. The handle 110 may thus be made with a stiffer or stronger material, e.g., an NBR material with a higher Shore A hardness in a range of 45 A to 55 A or more particularly, approximately 50 A. This stronger and possibly more durable material may thus be used for the handle 110 without sacrificing elasticity.

In addition, since the plurality of cavities 1000 are formed on a bottom surface 1010 of the handle 110, there is no risk of pinching a user or impeding sanding by a user. In prior sanding apparatuses, cuts or slits were formed on a top or periphery surface of the sanding block. These slits could pinch a user and make it more difficult to apply force to the sanding apparatus, especially on curved surfaces when the slits or cuts would open wider. This present embodiment with the plurality of cavities 1000 formed on the lower or bottom side 1010 of the handle 110 of the sanding apparatus 100 alleviates these problems while still increasing the elasticity of the handle 110. The base 150 may then be attached to the handle 110 using, e.g., industrial adhesive or heat or a combination thereof.

FIG. 11 illustrates an embodiment of a method 1100 for manufacturing the sanding apparatus 100. The method 1100 at step 1102 includes constructing a first mold for the handle 110, wherein the lower mold includes one or more rows 1024 of a plurality of pegs 1022. Each row 1024 of the pegs 1022 is configured to hold a manufacturing rod. The pegs 1022 may include slits to hold the manufacturing rod or include other configurations. A manufacturing rod is positioned on each of the rows 1024 of pegs 1022 at step 1104. An upper mold is positioned against the lower mold, e.g., using pressure exerted by screws, bolts, or other means, at step 1106. NBR material in a heated, liquid form is injected into the mold at step 1108 to form the handle 110 with the plurality of rod channels 120. The NBR material of the handle 110 cools and hardens to have, e.g., a Shore A Hardness in a range of 40 A to 60 A or more particularly, a Shore A Hardness in a range of 45 A to 55 A or more particularly, approximately 50 A.

At step 1110, a thin sheet of polycarbonate is manufactured to form the base 150. This step may be performed at any time, e.g., the base 150 may be prefabricated to the handle 110. At step 1112, the base 150 is attached to the handle 110, e.g., using an adhesive or heat or a combination thereof or other means.

The sanding apparatus 100 described herein overcomes the various disadvantages identified in the prior known sanding apparatuses, such as the known sanding block described in the above referenced U.S. Pat. No. 6,544,113. First, the sanding apparatus 100 described herein includes a thicker base member 150 comprised of polycarbonate. The base member 150 is still flexible and conforms to curved surfaces but is stronger than the thin stainless steel base member of the prior sanding apparatuses. The base member 150 herein is less prone to deformations and breakage and has strength to exert sufficient force on rough surfaces and protrusions to generate a smooth sanded surface.

Second, the sanding apparatus 100 described herein has rod channels 120 preformed in the rubber material of the handle 110 during manufacture. There is no need for brackets with bracket rod reception channels attached to the handle 110 as with the prior sanding apparatuses. There is no need for alignment between the brackets of the base member and the handle as in the prior sanding apparatus that creates additional steps and increases difficulties in manufacture and assembly. There is no bending or breaking of the brackets as in the prior sanding apparatus. Moreover, the elasticity of the handle 110 holds the rods 130 in position within the rod channels 120 without need of the rod reception tubes as in the prior sanding apparatus.

Third, the sanding apparatus 100 described herein has an improved profile to the handle 110 that provides for better and easier gripping. For example, a flat middle section W_(FT) of the handle 110 applies a more uniform force to a sanding surface when a user's hand, e.g. palm, presses along the flat middle section W_(FT). In addition, the flat middle section W_(FT) lowers a profile of the handle 110 for easier grasping by a user's fingers of the gripping portions 170 a-b, especially for smaller hands. The height H_(GP) of the handle 110 is also decreased to further ease grasping of the handle 110.

Further, in one embodiment, the sanding apparatus 100 described herein includes a plurality of cavities 1000 formed on a bottom surface 106 of the handle 110. The sanding apparatus 100 may thus comprise a stiffer material in the handle 110 and have an approximately similar overall elasticity when the plurality of cavities 1000 is implemented, e.g., the NBR material of the handle 110 may have a Shore A Hardness in a range of 40 A to 60 A rather than in a lower range of less than 40 A to 20 A. In prior sanding apparatuses, a plurality of cuts or indentations were positioned on a top gripping portion of the handle to enhance the flexibility of the handle portion. These cuts were prone to pinching a user and made it more difficult to apply pressure on the handle for sanding. The plurality of cavities 1000 described herein formed on the lower or bottom side 106 of the handle 110 alleviates these problems while still increasing the elasticity of the handle 110.

The sanding apparatus 100 described herein comprises two main parts, the handle 110 and the base member 150 that are attached adhesively or manufactured as one piece though dual injection molding. The sanding apparatus 100 thus has less parts and less complicated manufacturing than the prior sanding apparatus.

The sanding apparatus 100 may be used for paint removal and/or smoothing of panels or other surfaces of vehicles, such as automobiles, recreational vehicles, aircraft, boats, etc. In addition to vehicles, the sanding apparatus 100 may be used for sanding furniture, fences, or other objects. The sanding apparatus may be used for sanding metallic materials, wood, polycarbonate, ceramics, or other types of materials.

The sanding apparatus 100 described herein thus has many advantages over prior known sanding apparatus. Additional and/or alternative advantages may be present in the embodiments described herein. For example, certain benefits, other advantages, and solutions to problems have been described above with regard to particular embodiments; however, any benefit, advantage, solution to a problem, or any element that may cause any particular benefit, advantage, or solution to occur or to become more pronounced are not to be construed as critical, required, or essential features or components of any or all the claims.

In the foregoing specification, certain representative aspects have been described with reference to specific examples. Various modifications and changes may be made, however, without departing from the scope of the present invention as set forth in the claims. The specification and figures are illustrative, rather than restrictive, and modifications are intended to be included within the scope of the present invention. Accordingly, the scope of the invention should be determined by the claims and their legal equivalents rather than by merely the examples described. For example, the components and/or elements recited in any apparatus claims may be assembled or otherwise operationally configured in a variety of permutations and are accordingly not limited to the specific configuration recited in the claims. As such, the present teachings can be readily applied to other types of apparatuses and many alternatives, modifications, and variations will be apparent to those skilled in the art.

As may be used herein, the term “operable to” or “configurable to” indicates that an element includes one or more components, fasteners, or dimensions to perform one or more of the described or necessary corresponding functions and may further include inferred coupling to one or more other items to perform the described or necessary corresponding functions. As may also be used herein, the term(s) “coupled,” “coupled to,” “connected to” and/or “connecting” or “interconnecting” includes direct connection or and/or indirect connection through one or more other components. As may be used herein, the terms “substantially” and “approximately” provide an industry-accepted tolerance for its corresponding term and/or relativity between items.

As used herein, the terms “comprise,” “comprises,” “comprising,” “having,” “including,” “includes” or any variation thereof, are intended to reference a nonexclusive inclusion, such that a process, method, article, composition or apparatus that comprises a list of elements does not include only those elements recited, but may also include other elements not expressly listed or inherent to such process, method, article, composition, or apparatus. Other combinations and/or modifications of the above-described structures, arrangements, applications, proportions, elements, materials, or components used in the practice of the present invention, in addition to those not specifically recited, may be varied, or otherwise particularly adapted to specific environments, manufacturing specifications, design parameters, or other operating requirements without departing from the general principles of the same.

Moreover, reference to an element in the singular is not intended to mean “one and only one” unless specifically so stated, but rather “one or more.” Unless specifically stated otherwise, the term “some” refers to one or more. All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. No claim element is intended to be construed under the provisions of 35 U.S.C. § 112(f) as a “means-plus-function” type element, unless the element is expressly recited using the phrase “means for” or, in the case of a method claim, the element is recited using the phrase “step for.” 

1. A sanding apparatus, comprising: a flexible handle including a plurality of preformed rod channels, wherein the plurality of rod channels is preformed into the flexible handle; and a flexible base member including: a smooth top surface that is attached to a lower surface of the flexible handle; and a smooth bottom surface configured for attachment to an abrasive material.
 2. The sanding apparatus of claim 1, wherein the flexible base member comprises a polycarbonate material and wherein the flexible handle comprises a rubber material.
 3. The sanding apparatus of claim 1, further comprising: one or more inflexible rods configured for insertion into one or more of the plurality of preformed rod channels, wherein the one or more inflexible rods adjust a flexibility of the sanding apparatus.
 4. The sanding apparatus of claim 3, wherein an elasticity of the rubber material of the flexible handle holds the one or more inflexible rods in position within the one or more of the plurality of preformed rod channels.
 5. The sanding apparatus of claim 4, wherein the flexible handle is inflexible when at least one of the one or more inflexible rods is inserted in each of the plurality of preformed rod channels.
 6. The sanding apparatus of claim 1, wherein the flexible handle comprises: a top surface including at least a flat middle section W_(FT) extending lengthwise; a lower support portion including the plurality of rod channels; and a gripping portion including two indentations on opposing sides of the handle, wherein the gripping portion is positioned between the top surface and the lower support portion.
 7. The sanding apparatus of claim 2, wherein the flexible base member has a thickness in a range of approximately ⅛ inch to 1/16 inch.
 8. The sanding apparatus of claim 1, wherein the flexible handle has a height of approximately 1.4 to 1.6 inches.
 9. The sanding apparatus of claim 1, wherein the flexible base member has a width W_(BM) equal to or less than a standard width of commercially available standard sanding paper.
 10. The sanding apparatus of claim 1, wherein the flexible base member has a length L_(BM) of approximately one of: 8 inches, 16 inches, or 24 inches.
 11. A sanding apparatus, comprising: a flexible handle including a preformed plurality of rod channels, wherein the plurality of rod channels is preformed into the flexible handle; a flexible base member attached to a lower surface of the flexible handle, wherein the flexible base member is a polycarbonate material; and one or more rods configured for insertion into one or more of the plurality of preformed rod channels, wherein the one or more rods adjust a flexibility of the sanding apparatus.
 12. The sanding apparatus of claim 11, wherein the flexible base member comprises: a smooth top surface that is attached to the lower surface of the flexible handle; and a smooth bottom surface configured for attachment to an abrasive material.
 13. The sanding apparatus of claim 11, wherein the flexible handle comprises: a top surface including at least a flat middle section W_(FT) extending lengthwise; a lower support portion including the plurality of rod channels; and a gripping portion including two indentations on opposing sides of the handle, wherein the gripping portion is positioned between the top surface and the lower support portion.
 14. The sanding apparatus of claim 11, wherein the flexible base member comprises a polycarbonate material and wherein the flexible handle comprises a rubber material.
 15. The sanding apparatus of claim 11, wherein the flexible base member has a thickness of approximately ⅛ inch to 1/16 inch and wherein the flexible handle has a height of approximately 1.4 to 1.6 inches.
 16. The sanding apparatus of claim 11, wherein the flexible base member has a width W_(BM) equal to or less than a standard width of commercially available standard sanding paper.
 17. A method of manufacturing a sanding apparatus, comprising: manufacturing a flexible handle including a plurality of rod channels, wherein the plurality of rod channels is preformed into the flexible handle, by: in a lower mold, positioning one manufacturing rod of a plurality of manufacturing rods on each one of a plurality of rows of pegs; attaching an upper mold to the lower mold; and injecting a heated nitrile butadiene rubber (NBR) material in liquid form into the attached upper and lower molds, wherein the plurality of manufacturing rods forms the plurality of rod channels; and manufacturing a flexible base member by forming a thin sheet of polycarbonate material, wherein the thin sheet has a thickness of approximately ⅛ inch to 1/16 inch; and attaching the flexible base member to a lower surface of the flexible handle.
 18. The method of claim 17, wherein the plurality of rows of pegs forms a plurality of cavities on the lower surface of the flexible handle.
 19. The method of claim 17, further comprising: manufacturing at least one inflexible rod for each of the plurality of rod channels in the flexible handle.
 20. The method of claim 17, wherein the flexible base member is attached to the lower surface of the flexible handle using one of: an adhesive, a heat process, or a combination of an adhesive and a heat process. 